1. Technical Field
The present invention relates to techniques for ejecting a liquid from an ejection head toward an ejection target.
2. Related Art
A so-called ink jet printer, which is an example of a liquid ejecting apparatus, is capable of printing high-quality images by ejecting precise amounts of ink onto precise locations of an ejection target such as paper from fine ejection nozzles provided in an ejection head. If various types of liquids aside from ink (for example, a liquid in which the particles of a functional material are dispersed) are ejected onto a substrate, it is also possible to manufacture electrodes, sensors, biochips, and so on using this technique.
With this technique, the liquid, such as ink, that is supplied to the ejection head will thicken as time passes due to the moisture therein evaporating or the components thereof vaporizing from the ejection nozzles. Such thickening can make it difficult to eject precise amounts of the liquid. Accordingly, in the case where the liquid has thickened, an operation in which the thickened liquid within the ejection head is sucked out through the ejection nozzles and discharged (a so-called cleaning operation) is carried out by bringing a cap into contact with the ejection head, forming an airtight space around the ejection nozzles with the cap, and producing negative pressure within the cap using a suction pump.
The liquid sucked out from the ejection nozzles through the cleaning operation is fed to a waste liquid receptacle via a waste liquid channel and is accumulated in the waste liquid receptacle. Providing a waste liquid absorption material configured of a nonwoven fabric or the like that absorbs liquid within this waste liquid receptacle has been proposed (for example, JP-A-10-291328), and it is possible, by allowing the waste liquid absorption material to absorb liquid that has flowed into the waste liquid receptacle, to prevent liquid from leaking out from the waste liquid receptacle.
However, a waste liquid receptacle in which a waste liquid absorption material is laid has a problem in that the waste liquid absorption material cannot completely absorb the liquid if a large amount of liquid has flowed into the waste liquid receptacle in a short amount of time. For example, it is desirable, when one wishes to reduce the amount of time required to carry out the aforementioned cleaning, to increase the suction power of the suction pump; however, doing so causes a large amount of liquid discharged due to the cleaning to flow into the waste liquid receptacle in a short amount of time. Even if the waste liquid absorption material is designed with a volume that is large enough to absorb (accumulate) the amount of liquid discharged through the cleaning, the absorption of the waste liquid absorption material cannot keep pace with the inflow of liquid when such a large amount of liquid flows into the waste liquid receptacle in a short amount of time; this leads to a risk of liquid leaking from the waste liquid receptacle.